sw: layout: if fly's anchor moves forward, move fly off SwPageFrame

The problem is that on Show Changes->Hide Changes->Show Changes
in a 311 page document, the fly "Grafik1" was initially on page 203
but ends up on page 204, with a fly-sized gap on page 194.

In a 25 page cut down version of the bugdoc, on layout action 659
the fly's anchor SwTextFrame moves from page 21 to page 22, but
the fly remains in the SwPageFrame's m_pSortedObjs, because it's
not the anchor frame itself that moves but a distant previous frame,
and page 21 goes valid.

0  SwFlowFrame::PasteTree(SwFrame*, SwLayoutFrame*, SwFrame*, SwFrame*) (pStart=0x57c9e30, pParent=0xba15c50, pSibling=0x5a0f920, pOldParent=0xb057690) at sw/source/core/layout/flowfrm.cxx:586
1  SwFlowFrame::MoveSubTree(SwLayoutFrame*, SwFrame*) (this=0x57c9f48, pParent=0xba15c50, pSibling=0x5a0f920) at sw/source/core/layout/flowfrm.cxx:677
2  SwFlowFrame::MoveFwd(bool, bool, bool) (this=0x57c9f48, bMakePage=true, bPageBreak=false, bMoveAlways=false) at sw/source/core/layout/flowfrm.cxx:2061
3  SwContentFrame::MakeAll(OutputDevice*) (this=0x57c9e30) at sw/source/core/layout/calcmove.cxx:1831
4  SwFrame::OptPrepareMake() (this=0x57c9e30) at sw/source/core/layout/calcmove.cxx:399
5  SwFrame::OptCalc() const (this=0x57c9e30) at sw/source/core/inc/frame.hxx:1065
6  SwLayAction::FormatContent_(SwContentFrame const*, SwPageFrame const*) (this=0x7ffec0191b30, pContent=0x57c9e30, pPage=0xb9a1fd0) at sw/source/core/layout/layact.cxx:1833

In subsequent layout actions the anchor frame moves forward one
page at a time, until in action 665, when things get really interesting.

On page 24, the anchor text frame 582 is formatted for the first time,
and it moves the fly to page 24, after positioning it on the page.

2  SwPageFrame::MoveFly(SwFlyFrame*, SwPageFrame*) (this=0xb9a1fd0, pToMove=0x641d310, pDest=0x9125bb0) at sw/source/core/layout/flylay.cxx:972
3  SwFlyAtContentFrame::RegisterAtCorrectPage() (this=0x641d310) at sw/source/core/layout/flycnt.cxx:1432
4  SwAnchoredObject::SetVertPosOrientFrame(SwLayoutFrame const&) (this=0x641d468, _rVertPosOrientFrame=...) at sw/source/core/layout/anchoredobject.cxx:195
5  SwFlyAtContentFrame::MakeObjPos() (this=0x641d310) at sw/source/core/layout/flycnt.cxx:1466
6  SwFlyFreeFrame::MakeAll(OutputDevice*) (this=0x641d310) at sw/source/core/layout/flylay.cxx:223
7  SwFlyAtContentFrame::MakeAll(OutputDevice*) (this=0x641d310, pRenderContext=0x55b1f00) at sw/source/core/layout/flycnt.cxx:384
8  SwFrame::PrepareMake(OutputDevice*) (this=0x641d310, pRenderContext=0x55b1f00) at sw/source/core/layout/calcmove.cxx:375
9  SwFrame::Calc(OutputDevice*) const (this=0x641d310, pRenderContext=0x55b1f00) at sw/source/core/layout/trvlfrm.cxx:1791
10 SwFlyFrame::Calc(OutputDevice*) const (this=0x641d310, pRenderContext=0x55b1f00) at sw/source/core/layout/fly.cxx:2874
11 SwLayAction::FormatLayoutFly(SwFlyFrame*) (this=0x7ffec0191b30, pFly=0x641d310) at sw/source/core/layout/layact.cxx:1455
12 SwObjectFormatter::FormatObj_(SwAnchoredObject&) (this=0xa5c0d10, _rAnchoredObj=...) at sw/source/core/layout/objectformatter.cxx:286
13 SwObjectFormatterTextFrame::DoFormatObj(SwAnchoredObject&, bool) (this=0xa5c0d10, _rAnchoredObj=..., _bCheckForMovedFwd=false) at sw/source/core/layout/objectformattertxtfrm.cxx:135
14 SwObjectFormatter::FormatObjsAtFrame_(SwTextFrame*) (this=0xa5c0d10, _pMasterTextFrame=0x0) at sw/source/core/layout/objectformatter.cxx:408
15 SwObjectFormatterTextFrame::DoFormatObjs() (this=0xa5c0d10) at sw/source/core/layout/objectformattertxtfrm.cxx:337
16 SwObjectFormatter::FormatObjsAtFrame(SwFrame&, SwPageFrame const&, SwLayAction*) (_rAnchorFrame=..., _rPageFrame=..., _pLayAction=0x7ffec0191b30) at sw/source/core/layout/objectformatter.cxx:160
17 SwLayAction::FormatContent(SwPageFrame const*) (this=0x7ffec0191b30, pPage=0x9125bb0) at sw/source/core/layout/layact.cxx:1675
18 SwLayAction::InternalAction(OutputDevice*) (this=0x7ffec0191b30, pRenderContext=0x55b1f00) at sw/source/core/layout/layact.cxx:771

Nothing invalidates page 21 now that the fly is gone, and formatting
on page 24 is kind of pointless now because everything from page 21
on is wrongly positioned.  (It's possible to skip out of the main layout
action loop via SetNextCycle()/IsAgain(), but at this point it's in
layact:771 in the layout-all-the-visible-pages loop that follows
the main loop, and that one can't be cancelled.)

Then DoFormatObjs() is called on frame 582, and this calls
FormatAnchorFrameForCheckMoveFwd(), which formats previous frame 581,
splitting it and moving its follow along with 582 to page 25.

Here SwMovedFwdFramesByObjPos::Insert() is called, and now the anchor
text frame 582 cannot move back to page 24 because it's prevented by
SwMovedFwdFramesByObjPos::FrameMovedFwdByObjPos(), but that was all
based on the wrong assumption that the pages before 24 were
completely formatted (this happens in action 670).

Something later formats page 21 again, and so at the end there is a
fly-sized hole at the bottom of page 24, with frame 582 at the top
of page 25.

It won't help to detect a situation where the fly is on a page previous
to the page it's anchor frame is on in DoFormatObjs() because it was
actually moved to the same page in a previous formatting of the anchor
frame, in the same layout action.

To fix this, try to detect in SwLayAction::FormatContent() if the
anchor frame of any fly on the page has moved forward, and move those
flys off the page; this is enough for the 25 page document.

The 311 page document still has a hole on page 194 though; apparently
the last content frame on the page is never reformatted, so
invalidate its size.

Reviewed-on: https://gerrit.libreoffice.org/c/core/+/114066
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
(cherry picked from commit eb85de8e6b61fb3fcb6c03ae0145f7fe5478bccf)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/114519
Reviewed-by: Thorsten Behrens <thorsten.behrens@allotropia.de>
(cherry picked from commit 810f7e4e0b61ee7cb3a7d6a1b503782d7248a4b1)

tdf#141945 sw: layout: check master frame when moving fly forward

The problem is that in the finished layout the fly frames are
positioned on the first page but are in SwPageFrame::m_pSortedObjs
of the second page.

Don't use FindPageFrameOfAnchor() because that looks up the follow-frame
that contains the anchor position.  This was unintentional; the idea
was to get flys anchored in subsequent paragraphs out of the way.

This situation where it's on a follow-frame of the same paragraph is
more complicated and less obvious, so don't try to solve it now.

(regression from eb85de8e6b61fb3fcb6c03ae0145f7fe5478bccf)

Reviewed-on: https://gerrit.libreoffice.org/c/core/+/115100
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
(cherry picked from commit 30512746c182b52f37f9a818d4e206c98e715cb7)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/115080
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
(cherry picked from commit 41f68b652eb1ccdd4941e2270426461da8e66417)

Change-Id: I232c6b305e8593bfecd885c36058777f3980f82f
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/115763
Tested-by: Michael Stahl <michael.stahl@allotropia.de>
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>

0 files changed, 0 insertions, 0 deletions